Fuse for projectiles



Patented Aug. 30, 1938 FUSE FOR PROJECTILES Nicolas Emilien Methlin, Paris, France, assignor to Schneider & Cie, Paris, France, a joint-stock company of France Application November 19, 1936, Serial No. 111,719 In France and in Great Britain November 29, 1935 8 Claims. (Cl. 102-39) This invention relates to a percussive head fuse wherein application is made of the known principle of making the whole of the firing mechanism and a centrifugal safety device, rendering operation impossible until the withdrawal of the said safety device, independently rotatable with respect to the projectile body, so as to delay the operation of the safety device and consequently the arming of the fuse until, due to the rotation of the whole of the independent element, the centrifugal force reaches a value sufficient for the withdrawal of the said safety device.

The object of the present invention is to provide a head fuse in which the said principle is applied and which is characterized by a special arrangement of the elements of the fuse body, that is to say of the element secured to the projectile on the one hand, and of the element comprising the whole of the firing mechanism and the centrifugal safety device on the other hand.

According to the invention, the part of the fuse body which is rotatable relatively to the projectile, and contains the whole of the firing mechanism and the centrifugal safety device, carries the nose of the said fuse body, and is provided with a rear appendage carrying a retaining member, such as a collar, which is detachable for assembling, means such as balls to reduce the friction preferably being interposed between the fixed part and the rotatable part of the fuse.

This method of constituting the parts of the fuse body results not only in a considerable facility in assembling the fuse, but also in a considerable independence between the fixed part and rotary parts of the fuse body, the inertia of the rotary parts being utilized as fully as possible.

The firing mechanism and the centrifugal safety device may have various forms, but in Figures 1 and 2 of the accompanying drawing a preferred form of construction has been shown in combination with the improved manner of constituting both the fixed part and the rotary parts of the fuse body. The figures show the fuse in sectional elevation in two positions of the firing mechanism, Figure 1 showing the firing mechanism and the safety device at rest, whilst Figure 2 shows the segments of the safety device withdrawn under the effect of the centrifugal force, and the corresponding position of the sliding ring or sleeve combined with these segments.

As shown in the drawing, the fuse body is constituted by a fixed part a screwed into the ogive of the projectile and by part b1, which is movable relatively to the fixed body a and is fitted in the latter. This part b1, comprises screw-threaded rear and front extensions to which are screwed a detachable retaining collar b3, and the nose be of the fuse body. The said movable parts h1-bzb3 are simply supported on a shoulder" on of the part a, for example by a ring of balls 0. The part In is centered in the front of the part a, for example by balls d lodged in a groove in the part bi and bearing on the internal wall of (1. During the fiight of the projectile, the pressure exerted on the nose ha is sufficient to press the whole of b2b1b3 on the balls 0, while at any time the escape of the movable parts of the fuse body forwardly is rendered impossible by the collar be disposed opposite a shoulder oz of the part a.

In the constructional example shown, the firing mechanism and the safety device disposed in the movable part D1 are constituted as follows:

The firing mechanism comprises a plunger e carrying the percussion cap f, and segments g of known construction encircled by a flexible winding 91 and engaging, at rest, a groove 61 of the said plunger e. The safety device is completed by a sleeve 71., the rear edge of which is normally maintained pressed against the segments g by one of the ends of a spring hi, the other end of which bears against a shoulder of the nose part b2 of the fuse body. The sleeve it acts as a guide to the plunger e and its forward end is pierced by a hole for the passage of the point 21 of the striker, the front edge of the sleeve forming a retaining support or abutment for the striker 2'. At rest, a shoulder on the latter is held, as shown in Figure 1, between the front edge of the sleeve h and a shoulder of the nose part be. If desired, the striker may be attached to be by a retaining member, such as a pin.

In the case in which the striker z is not attached to b2, it is necessary to provide an easily destructible cap 9' which protects the striker support from the pressure of the air during the flight of the projectile.

It is easy to see that this manner of constructing the fixed and movable parts of the fuse body permits easy mounting in the fixed part a of the whole of the rotary unit b1-b2 -b3, including the firing mechanism and the safety device, the entire fuse being rendered ready for use merely by placing in position the collar b3, made in the form of a nut, after inserting the other parts of the movable unit in the fixed part.

The operation of the fuse does not present any peculiar features.

During the first part of the trajectory, the withdrawal of the safety device under the eifect of the centrifugal force by the moving apart of the segments 9 is delayed by the fact that the movable parts b1b2 3 do not immediately participate in the rotation of the projectile. It is only at the end of a certain time that driving of the movable part carrying the safety device and firing mechanism becomes sufiicient for the effect of the centrifugal force to make itself felt on the segments 9 The latter then pass from the position which they occupy in Figure '1 into that shown in Figure 2, while the sleeve h, under the action of the spring hi, can then move rearwardly and interpose itself between the segments and the plunger of the percussion cap support, thus preventing any subsequent untimely inward movement of the said segments. The fuse is then armed and, in the known manner, may operate by the driving in of the striker or by the combined driving in of the striker and the inertia of the movable percussion cap support.

What is claimed is:

1. A percussive head fuse for projectiles comprising a rear fuse body element adapted to be fixed to the projectile, a front fuse body element including a percussive firing mechanism and a centrifugally responsive safety device for normally retaining said firing mechanism in inoperable condition, means for mounting said front element for rotation relatively to said rear element, and a retaining member connectible to and removable from said front element when the latter is in as sembled relation with said rear element for preventing forward movement of said front element relatively to said rear element.

2. A percussive head fuse for projectiles comprising a rear fuse body element adapted to be fixed to the projectile, a front fuse body element including a percussive firing mechanism and a centrifugally responsive safety device for normally retaining said firing mechanism in inoperable condition, means for mounting said front element for rotation relatively to said rear element, said front element having a rearwardly extending portion passing through said rear element, and a retaining co1lar carried by said rearwardly extending portion for preventing forward movement of said front element relatively to said rear element.

3. A percussive head fuse for projectiles comprising a rear fuse body element adapted to be fixed to the projectile, a front fuse body element including a percussive firing mechanism and a centrifugally responsive safety device for normally retaining said firing mechanism in inoperable condition, means for mounting said front element for rotation relatively to said rear element, said front element having a rearwardly extending portion of reduced diameter passing through said rear element, and a retaining collar connectible to and removable from said rearwardly extending portion for preventing forward movement of said front element relatively to said rear element.

4. A percussive head fuse for projectiles comprising a rear fuse body element adapted to be fixed to the projectile, a front fuse body element including a percussive firing mechanism and a centrifugally responsive safety device for normally retaining said firing mechanism in inoperable condition, means including anti-friction members for mounting said front element for rotation relatively to said rear element, and a retaining member connectible to and removable from said front element when the latter is in assembled relation with said rear element for preventing forward movement of said front element relatively to said rear element.

5. A percussive head fuse for projectiles comprising a rear fuse body element adapted to be fixed to the projectile, a front fuse body element including a percussive firing mechanism and a centrifugally responsive safety device for normally retaining said firing mechanism in inoperable condition, means for mounting said front element for rotation relatively to said rear element, said front element being screw-threaded at both its forward and rear ends, a fuse nose threaded to said forward end, and a retaining collar threaded to said rear end in such position as to prevent forward movement of said front element relatively to said rear element.

6. A percussive head fuse for projectiles comprising a rear fuse body element adapted to be fixed to the projectile and having a recess formed in the forward end thereof, a front fuse body element including a percussive firing mechanism and a centrifugally responsive safety device for normally retaining said firing mechanism in inoperable condition, means for rotatably supporting said front element in said recess, said front element having a rearwardly extending portion passing through a bore in said rear element to the rear face thereof, and a retaining member connectible to and removable from said rearwardly extending portion when said front and rear elements are in assembled relation.

'7. A percussive head fuse for projectiles comprising a rear fuse body element adapted to be fixed to the projectile and having a recess formed in the forward end thereof, a front fuse body element including a percussive firing mechanism and a centrifugally responsive safety device for normally retaining said firing mechanism in inoperable condition, means including anti-friction members for rotatably supporting said front element in said recess, said front element having forwardly and rearwardly extending screwthreaded portions, a fuse nose threaded to said forwardly extending portion, and a retaining co1- lar threaded to said rearwardly extending portion in such position as to prevent forward movement of said front element relatively to said rear element.

8. A percussive head fuse for projectiles comprising a rear fuse body element adapted to be fixed to the projectile, a front fuse body element including a percussive firing mechanism and a centrifugally responsive safety device for normally retaining said firing mechanism in inoperable condition, means for mounting said front element for rotation relatively to said rear element, and a retaining member connectible to and removable from said front element when the latter is in assembled relation with said rear element for preventing forward movement of said front element relatively to said rear element, said firing mechanism and centrifugally responsive safety device comprising a striker, a percussion cap carrier and cap mounted therein, a sleeve in telescoping relation with said carrier, the forward end of said sleeve normally holding said striker in inoperable position, centrifugally responsive segments normally engaged in a groove formed in said carrier and forming an abutment for the rear end of said sleeve, and spring means for continuously urging said sleeve rearwardly whereby, when said segments move outwardly in response to centrifugal force, said sleeve is moved rearwardly to a position enabling percussive contact between said striker and cap upon impact of the projectile.

NICOLAS EMILIEN METHLIN. 

